A man who booed during a Welcome to Country at an Anzac Day dawn service has refused to apologise while being sentenced in court. 

Eli Joseph Toby pleaded guilty in Sydney's Downing Centre Local Court on Wednesday to one count of committing a nuisance at a war memorial for booing loudly while Uncle Ray Minniecon was delivering the Welcome. 

When asked by Judge Greg Grogin whether he was sorry for what he had done, Toby said he had 'mixed feelings'. 

'I'm sorry it has caused such an uproar and I'm sorry to my family,' he said. 

Toby said he was expressing his belief that Welcome to Country ceremonies were overdone and should not be performed at Anzac Day commemorations. 

'My behaviour was not designed to be offensive to Aboriginal or Indigenous people,' he said. 

'My booing of the Welcome to Country was my vocal expression ... of a feeling that is shared by (many).'

Judge Grogin repeatedly pressed Toby on whether he was apologetic for disrupting the ceremony.

'Are you sorry? Obviously not,' the judge said when Toby would not answer.

The judge told Toby there were many more appropriate ways he could have expressed his dissatisfaction and that he disturbed a deeply solemn ceremony for thousands of people.

'You broke a tradition, you broke a deeply sensitive moment to express your thoughts when nobody asked for them,' Judge Grogin said.

'Your actions, especially that you're unable to say you're sorry for what you did, show an ignorance ... as to what Anzac Day really means.'

Toby was convicted and fined $880.

He was arrested on Anzac Day and several others were moved on from the 11,000-strong crowd at Martin Place, Sydney.

After the acknowledgement - punctuated by booing - finished, a chorus of applause resounded for an extended period in support of Uncle Ray.

'We do have laws to try and deter people from this but it seems like these people still want to be lawless,' the pastor and veteran said after the ceremony.

'They just need to realise their place in this country ... and show their deepest respect.'

The booing attracted condemnation from around the country, with RSL Australia National President Peter Tinley labelling it 'loutish behaviour' that was 'grossly disrespectful' to First Nations people. 

NSW Premier Chris Minns expressed his disappointment with the few in the crowd who chose to mar the sombre occasion with ugly scenes. 

'This is a day to honour sacrifice,' he said at the time.

Boos and heckling were also heard at Anzac Day ceremonies in Perth and in Melbourne. 

Defence Minister Richard Marles said it was 'deeply disappointing' behaviour at a time when the country should be acknowledging the contributions Indigenous Australians have made to the nation's defence.

'What we have seen with this booing is a disgrace, and it is deeply disrespectful to everyone actually who is participating in Anzac Day and particularly to that history,' he told the ABC.

The view was echoed by opposition defence spokesman James Paterson, who said the heckling was completely inappropriate considering the service of Indigenous Australians who fought in uniform.

'Whatever your views about Welcome to Country, it is never appropriate to boo in an Anzac Day ceremony, which is our most sacred moment as a nation,' he said.

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